Alert archive / Maryland / Mesoscale Discussions in 2020

Mesoscale Discussion 1122

July 6, 20205 states

The Storm Prediction Center issued this mesoscale discussion at Jul 6, 2020, 6:25 PM EDT for 5 states. It was in force for 2 hr.

The area

The outline as issued.

The facts

Issued: Jul 6, 2020, 6:25 PM EDT (22:25 UTC)
Expired: Jul 6, 2020, 8:30 PM EDT
In force: 2 hr
Issued by: the Storm Prediction Center
Concerning: Severe thunderstorm watch 333

All 54 counties

Kent County, DE, New Castle County, DE, Sussex County, DE, Anne Arundel County, MD, Baltimore County, MD, Calvert County, MD, Caroline County, MD, Carroll County, MD, Cecil County, MD, Charles County, MD, City of Baltimore, MD, Dorchester County, MD, Harford County, MD, Howard County, MD, Kent County, MD, Montgomery County, MD, Prince George's County, MD, Queen Anne's County, MD, Saint Mary's County, MD, Somerset County, MD, Talbot County, MD, Wicomico County, MD, Worcester County, MD, Atlantic County, NJ, Camden County, NJ, Cape May County, NJ, Cumberland County, NJ, Gloucester County, NJ, Salem County, NJ, Chester County, PA, Delaware County, PA, Lancaster County, PA, Montgomery County, PA, Philadelphia County, PA, Accomack County, VA, Arlington County, VA, Caroline County, VA, City of Alexandria, VA, City of Fairfax, VA, City of Falls Church, VA, City of Fredericksburg, VA, City of Manassas, VA, City of Manassas Park, VA, Culpeper County, VA, Essex County, VA, Fairfax County, VA, King George County, VA, Lancaster County, VA, Northumberland County, VA, Prince William County, VA, Richmond County, VA, Spotsylvania County, VA, Stafford County, VA, Westmoreland County, VA

The radar

The Dover AFB radar (KDOX), 87 km from the middle of the area, began a volume at 22:27 UTC, the scan nearest the moment this went out.

Open the radar archive at this moment

The archived warnings, watches and discussions in force at that minute are drawn over the scan, this one among them.

The nearest sounding before it

Washington/Dulle, VA (KIAD), launched 12:00Z, 10.4 hours before the alert went out and 85 km from the middle of its area. This is the routine balloon launch nearest before it, the air the forecaster had in hand, not a measurement taken for the alert.

Skew-T log-p

Temperature in red, dew point in green, the mixed-layer parcel dashed.

Hodograph

The wind turning with height, colored by layer: ground to 1 km, 1 to 3 km, 3 to 6 km, 6 to 10 km.

Mixed-layer CAPE: 1250 J/kg
Mixed-layer CIN: -133 J/kg
Mixed-layer LCL: 1150 m above ground
0-6 km bulk shear: 21 kt
0-1 km storm-relative helicity: 62 m²/s²
0-3 km storm-relative helicity: 57 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

The text

As transmitted.

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SPC that day

Everything else SPC issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Jul 6, 12:33 PM EDT	Mesoscale Discussion	SPC	Kent, New Castle, Sussex	3 hr
Jul 6, 1:38 PM EDT	Severe Thunderstorm Watch	SPC	Kent, New Castle, Sussex	9 hr
Jul 6, 4:33 PM EDT	Mesoscale Discussion	SPC	Kent, New Castle, Sussex	117 min

Nearby

Mesoscale Discussions in Maryland, 2020 Mesoscale Discussions in Virginia, 2020 Mesoscale Discussions in New Jersey, 2020 Every mesoscale discussion in 2020

Sources

The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.